The biggest worry was to find a ball-handler and orchestrator, and one who could play the high pick and roll beautifully. Melo isn't the ideal pick and roll player. Instead, Melo can stick to his strengths. He could get the ball in the high post and move more without the ball.
I think Melo's role could mimic when he was on team USA. he was more a spot up shooter and post threat facing few double teams. I can only imagine the court opening up for him. He'll have better looks. I don't think he'll face double and triple teams as often. He doesn't have to score 25. Melo can drop 15-18 and the Knicks will be fine.